Melody is 42w push pull. While it sounded great with mine it still leaves you wanting.
The NS-2000 would eat that up easy.
you’ll be looking at 50w per channel minimum.
But as @kelossus said you’d be better off with SS.
@Grizzly has a B-1 that would be a match made in heaven

No not see through. I guess you could if you wanted to protect the original finish. Mostly it’s to make black speakers red or white speakers blue. Whatever
Any colour you want.
And similar process yes. The reason you want a good wrapper is that they can do tricky seams on speakers very well.

Yep. The floors in containers can be toxic and often need to be replaced. They are treated for weather and pests etc. Also containers need to be treated to be condensation resistant. As well as all of the above.
I’d say by the end of your experiment you’d end up with a claustrophobic unhappy space that cost a lot. Could you look at de-coupling your HT better?